Machine for sharpening mowing-machine knives



(Mode1.) 2Sl1eets Sheet 1.

S. McGAY.

MACHINE FOR SHARPENING MOWING MACHINE KNIVES. No. 292,244. Patented Jan. 22, 1884.

(ModeL) 2 Sheets-Sheet 2.'

' S. McOAY.

MACHINE FOR SHARPENING MQWING MACHINE KNIVES.

I Patented q g n.

f-mfnassss.

Nv PEIERS, Hwm-umo lw. Wnhingwn. 0.6.

UNITED STATES PATENT OFFICE.

srnnonn CGAY, or TOPEKA, KANSAS.

MACHI NE FOR SHARPENING MOWING-MACHINE KNIVES.

SPECIFICATION forming part of Letters Patent No. 292,244, dated January 22, L584.

Application filed October 22.1883. lModel.)

To all whom it may concern.-

'Beitknown thatI, SPENCER MCCAY, of Topeka, in the county of Shawnee and State of Kansas, have invented certain new and useful Improvements in Machine for Sharpening Mowing-Machine Knives; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it pertains to make and use it, reference being bad to the accompanying drawings, which form part of this specification.

My invention relates to an improvement in machines for sharpening mowing-machine knives; and it consists, first, in the swinging frame, which consists of a pivoted part carrying the two guiding-pulleys, anda second part, which is pivoted to the first one, and which has the grinding-wheel journaled in its outer end, whereby the wheel can be moved both horizontally and vertically; second, in the combination, with the emery-wheel, which is journaled'in the outer end of the frame, of fingers or guides, which pass through the frame and are adjustable therein; third, in the arrangement and combination of parts,which will be more fully described hereinafter.

Figures 1 and'2 are side elevations of a machine embodying my invention, taken from opposite sides. Fig. 3 is aplan view. Fig. 4is an inverted View of the outer end of the frame. Fig. 5 is an end view of the outer end of the frame. Figs. 6 and 7 are detail views of the table and its attachments.

A represents a suitable stand or frame, which is adapted to have the operator sit upon it at B, and upon the top of which frame, at the opposite endfrom the seat B, are the two standards O. Journaled in between these two standards is the shaft D, which is provided with the large grooved pulley E and the small pulley F. Also placed uponthe top of the table, near its center, is the standard G, upon which the large driving-wheel H is pivoted. Over this large driving-wheel and the small grooved pulley on the shaft is passed the driving-belt I, which communicates motion to the other parts ofthe machine.

Piv oted uponthe top of one of the standards 0 is the support J, which moves freely back and forth in a line'with the frame or table,

and which has a hole or socket in its upper end to receive the pivot or projection upon the lower part of the hinge L. To this hinge or pivoted part Lis pivoted the long arm or lever M, in the outer end of which is pivoted the emery-wheel N. Secured to the side of the hinge is the bar or arm L, which carries at its free end thegrooved pulley 0. Upon the same pivot as the bar or arm is secured alarger grooved pulley, P, and over these two pulleys O P, the large grooved pulley upon the driving-shaft, and the pulley Q upon the emerywheel, passes the driving belt or band B, in the usual manner. The great advantage of the pivoted hinge at the inner end of the frame consists in enabling the frame to be moved forward and back, up and down, and in any direction that may be preferred. If this hinge were not in use, then the frame would have simply a backward, forward, and vertical play and nothing more. By giving the swinging frame a lateral movement the emery-wheel can follow the bevels or inclines of the teeth without having to move the teeth for this purpose. \Vhere the emerywheel can be.moved, as here shown and described, the operator has but to clamp the knife which is to be ground rigidly in position upon the table, and then move the wheel back and forth over those places where it is needed, thus saving the operator a great deal of time and labor and reducing the amount of skill which is necessary to properly grind the knife. 'Passed down through the outer end of the swinging frame, upon each side'of the emerywheel, is a set-screw, S, which can be raised or lowered, so as to regulate the depth to which the emery-wheel shall sink. These screws may travel along upon the knife itself, or upon the triangular-shaped guide T, which is clamped upon the top of the table. above the knife.

Secured in the outer end of the frame, but in the rear of the emery-wheel, by means of a set-screw, U, is the elastic forked guide V, the prongs of which extend along upon opposite sides of the emery-wheel, and serve to rest upon the knife and support the grinding-wheel and the outer'end of the pivoted frame. This guide being yielding, when a pressure is ex erted upon the outer end of the frame, the

grinding-wheel is forced downward in contact ICO with the edge of the knife for the purpose of cutting an even bevel on every section ortooth. The depth of the cut, or the distance the wheels shall be forced downward, is regulated by the set-screws S. The yielding guide can be used without the set-screws, if so desired, but the same uniformity of bevel and cut cannot be obtained, and a greater skill is then required.

In order to turn the knife up so asto expose the edges of the sections in different positions the top 7 of the table is pivoted upon the supports X, so that the top can be turned up, as shown. Passing through the top of this table are anumber of clamping devices, Y, by means of which the knife is clamped in position, and also clamped upon the top of the table is a V-shaped guide, T. This guide is placed upon the top of the knife, and can be rigidly clamped in position by means of a setscrew, A, which passes up through thetable and the corner or point of the guide. The angle at which the outer ends or points of this guide extend over the top of the knife is regulated by the set-screw A, which passes up through the table and bears against the point of the guide beyond the set-screw, by which it is clamped in position. 13y limiting the angle of this V-shaped guide the emery-wheel can be brought more perfectly in contact with certain portions of the sections than can be done if the guide extends horizontally outward. Suitable projections, a, are formed upon the under side of this guide, and these projections upon the top of the knife or section help support the guide in position.

Instead of abeltbeing used to run the emerywheel upon the swinging frame, gear-wheels or any other suitable devices may be used for this purpose, as I. do not limit myself in this respect.

Having thus described my invention, I claim- 1. In a machine for grinding mowing-machine knives, the combination of the support 0, the part J which is pivoted thereon, and which supports the two guiding-pulleys, with the pivoted part M, which carries the grindingstone in its outer end, whereby the stone has both a horizontal and vertical movement, substantially as shown.

2. The combination, with the emery-wheel, of an elastic forked guide, which extends upon both sides of the wheel, substantially as described.

3. In a machine for grinding mowing-machine knives, the combination of the movable frame, having the grinding-wheel journalcd on its outer end, with the forked guide, which extends upon both sides of the wheel, and the set-screws S, substantially as set forth.

4. The combination of the pivoted table with the guide T, the set-screws A A, and the projections aon the under side of the guide, substantially as specified.

' 5. The combination of the table, the V- shaped guide, provided with a clamping device, and a set-screw for changing the angle at which the V-shaped guide is held in relation to the knife, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

SPENCER McCAY.

\Vitnesses:

\VIL'LIAM R. IIAZEN, E1). A. B.\'l\VELL. 

